Flexible bellows seal for flanged pipe joint



Dec. 2, 1958 Filed Feb l0,

K. B. BREDTS'CHNEIDER 2,862,729

FLEXIBLE BELLOWS SEAL FOR FLANGED PIPE JOINT 1955 2 Sheets-Sheet 1jwezgian ,WZ Jrastlueader:

8 K. B. BREDTSCHNEIDER 29 I I FLEXIBLE BELLOWS SEAL FOR FLANGED PIPEJOINT Fi led Feb. 10; 1955 2 Sheets-Sheet 2 for attachment to a pipeline. A relieved annular portion at 9'a11d 11 is provided to receive therespective comd s P "to" 9 2,862,729

7 I a Patented Dec. 2,- 195 8 plementary bellows or rings 12 and 13. Thebellows or rings in order to impart comparative flexibility thereto 2862 729 are formed on both exterior and interior portions with 7 annularserrations 14 and 15 respectively. In abutting FLEXIBLE BELLOWS SEAL FORFLANGED relation to each other and preferably integral therewith PIPEJOINT. the respective end disposed flanges 16 and 17 are proa vided, theflanges having the suitably finished surfaces 18 K ii gfig gg?iff ggiggi gah gg'i fiii (1mm and 19 to form a fluid tight sealing surfacetherebetween. t The outer periphery of'the flanges 16 and 17 are'joinedApplication February 10, 1955, Serial No. 487,242 by an annularlydisposed fusion weld 21. An annular chamber 20 provides for addedflexibility in the flanges t 3 Claims (CL 285-114) without impairing theeffectiveness of the said weld.

At each outer end portion of the respective bellows, V as at 22 and 23,the latter members are either welded or Thisinvention relates to a liptype of flanged joint for otherwise suitably brazed or sealed in fluidtight relation conveyanceoffiuids and more particularly is concerned byattachment to the respective flanges 1 and 2 at the with ,a form ofcoupling embodying the invention. outer end limits of the respectiveflange recesses 9 and 11. In connection with the use of absolutely tightjoints on It has been discovered that in order to avoid placingexceedingly high temperatures and pressures, the matter any excessivelongitudinal or torsional stresses upon the of providing such jointperformance becomes a diflicult sealing bellows during the completion ofsuch joint asand frequently quite critical problem, particularlyrealizsembly when the respective flanges 1 and 2 are being ing the needfor handling not only very high temperatures, drawn together to form thefluid-tight assembly that this but also possessing in such jointsdesirable flexibility in can be done safely, conveniently andeconomically by response to'changes in temperature as, for example,those interpos-ing as a filler means between the flanges 5 and 6 whichmay occur when the line is out of operation term a plurality ofannularly spaced-apart ring members 24 porarily or if a fluid issubsequently used at substantially having the apertures 25 to fit overthe bolt studs 3 as lower temperatures in the same pipe line during thecourse shown. Thus, it will be clear that with the proper and ofprocessing. accurate selection for each bolt stud of the necessary Ithas been discovered that if relatively flexible meminsert members orfiller pieces 24 with respect to their bers are installed within andbetween substantially fixed overall length the pipe joint can beproperly drawn up or rigidly mounted coupling members, such as a pair ofwithout danger of overstressing the bellows. The bolts relatively heavyflanges, a type of joint is produced may then be drawn up additionallyover and above that which possesses such desirable flexibility 'as aboverestress originally applied during the course of fabricating ferred tofor the many variable pressure and high temperaor joining together ofthe bellows halves. Thus, it is ture conditions encountered. clear thata stiff and substantial coupling has been pro- Therefore, it is animportant object 'of this invention vided with the p l adequatelyvpreteeted against any to provide a lip joint in which internal fillerpieces are in e nal pipe bending stress. e t e j installed between apair of coupling halves, such as flanges, In this connection, f'desired,and as a substitute for whereby after-the desired tightening load isapplied either the filler members there may be placed between the bybolts or similar means for drawing the flanges together, 40 boltsWedge-like members f l r configuration to support pieces of a characterhereinafter described are maintain the flanges 5 a 6 p t a y p r erintroduced into the space between the two coupling halves S ConditionsOf pr rm n d l ading to substantially bring a clearance between theflanges to It should, of u pp r thatt w SPeeifie zero. manner in which.the weld seal at 21 -is accomplished may It is a further object toprovide that after such ste is y depending p the degree of ili y ir in tk n, th b l or ther drawing means are, stressed the bellows assembly. Inthis connection, attention is further by suitable tightening and thuscreating ultimately directed to a modified form of the ture Shown in astifl? or rigid coupling with the inner seal ring as here- 2 in which,in all respects the manner 0 making t inafter described. beingsubstantially protected against flanges, assembling them and creatingthe fluid tight external pipe bending stresses, such as those that arebellows seal within the recesses of the flangesis identical normallyencountered with a valve/or fitting applied/in a to that described inconnection W g- However; in pipeline, o the instant modificatiomthebellows instead of having the Other objects and advantages will becomemore readily annular transverse flanged portion as described at 16 andapparent upon proceeding with the description of the de- 17in 1 theintegral flanges of an l r Curved i embodying my i ti i hi hcross-sectional form in which the abutting surface con- Fig. 1 is asectional assembly view of a preferred emtact at 26 and 27 isallgnlented y means of the an ular bodi t f th i ti curved and turned-upouter ring portions 28 and 29 re- Fig. 2 is a fragmentary sectional viewof a difi d spectively, the latter being sealed at their outer limits asform. at 31 and thereby creating an annular chamber 32 within Fig. 3 isa sectional assembly view of a further modified which the desired degreeof flexibility y he imparted form and which is outwardly sealed by meansof the annular Similar reference numerals refer to similar parts Weldthroughout th several i It will, of course, be appreciated that in thismodified Referring now to Fig. l, in order to make a preferredconstruction, as distinguished from the structure of Fig. 1, f f j i t,h complementary flanges 1 d 2 are 6, additional flexibility is imparted,such that in the event a l d h i i bl drawing-up means, h as h slightseparation of flanges should occur of the surfaces bolt studs 3 and nuts4, extending through the flanges 5 26 and 27, it is quite unlikely thaty line foreign matter and 6, the flanges being provided with the usualpassage or sediment entering between such surfaces would be ob- 01 ports7 and 8 forming a throughnway the respective jectionable in that noadded stress Would be placed upon latter passages. Suitable connectingends 10 are provided the Weld Beeause 0f the degree of fleXing P vid dby the curved annular sections of the bellows, at 28 and 29, such addedstresses would be readily absorbed.

Further, the annular chamber 32 could easily receive such materials fromthe line and under certain conditions permit the surfaces 26 and 27 toagain be joined without destroying the efliciency of the joint.

In a still further modified form as shownin Fig. '3, instead ofemploying bolts to draw the flanges 33 and-34 together a split clampmember 35 -may be used, held together 'by 15' transversely extendingbolts indicated generally at 36 to enclose as at 37 the flanges 33 and34 in comparatively snug relation and also engaging the annularprojections 38. In this modification, the interposed gasket may consistof a pair of serratedsleeves 39 with serrations on the inner and outersurfaces forthe reasons hereinabove described as indicated at 41 and 42and being weldably attached or otherwise connected as at 43 to therespective flanges 33 and34. Suitable contact surfaces are formed at 44and'45 by means of annularly curved integral portions 46 and 47. Thechamber48 on its outer limits is weld sealed as at 49. The flangedportions as at 46 and 47 are snugly retained at their fillet portions51'and 52 respectively, and preferably the split clamp 35 is providedwith an anular extension or projecting portion '53 to serve as a meansfor snugly retaining the weld portion 49 against outward expansion ordeflection. In this type of structure, it will of course be appreciate'dthat the projecting member 53 of the split clamp serves as an interposedfiller thereby to prevent pipe line stress being transmitted directlyand longitudinally against the assembled gasket halves '39 and thereforein this capacity serves in the same manner as the interposed fillerpieces 24 described in connection with the other views.

It will thus become apparent that three types of joints provide a verysubstantial means of protection for the relatively more fragile type ofsealing element provided by the co-acting bellows shown. The pipe jointitself may be subjected 'to severe structural line stresses due tothermal changes or misalignment and increases in pressure, or, perhaps,other mechanical distortion in the pipe line itself. Yet the flangesbecause of the substantial reinforcing character are provided by-thefiller members 24 will readily absorb such stresses or strainswithout'objectionably affecting the eificiency of the bellows assembly.Under certain conditions, the flange portions 16 and 17 and the ringsfitted in chambers 9 and 11 may be made integral with the members 1 and2.

It will, therefore, become apparent that While only three forms of myinvention have been shown'as preferred embodiments, other relatedassemblies may be employed using various shapes or forms of sealswithout changing 'or departing from the scope of the invention.

Accordingly, its scope should be measured by the appended claims.

I claim:

1. In a combined mechanically assembled and weld sealed joint'comprisinga pair of axially spaced aligned the outer annular end limits of thesaid inserts being fixedly sealed to end annular limits of the flangerecesses, the said inserts having enlarged annular portions lyingimmediatley outside of said flange recesses and between the saidflanges, the latter enlarged annular portionshaving oppositely disposedcurved lip port-ions joined in fluid sealing relation radially andaxially outside of said recesses and in spaced apart annular relation tothe end abutting connection of said inserts, the inner end adjoininglimits of the inserts comprising the lip portions being substantiallyreduced in thickness with the adjoining limits having sharp annularcorners forming feather edges for initiating a weld seal, the lip"portions and weld seal forming outside of the insert end abuttingconnection a sub stantially annular chamber, .the outer peripherallimits of the said chamber forming'the weld seal and being defined by anannular thin weld joining the curved lip portions of the said insertsinfluid tight relation, and removable spacer means cooperating with saidannularly mounted means on the flanges'to hold the latter members inpredetermined spaced apart axial relation when mounted in said fixedassembly.

2. The subject matter of claim 1, the said oppositely disposed curved'lip ped portions bein'g inturned'and of hook-like configuration incross-section'to form the said substantially annular chamber. p j

3. The subject matter of claim 1, the said removable spacer meanscomprising a split'clamp member engaging annular projections on theflanges.

References Cited in the file of this patent

